Problem: A driver may report that a growling noise is coming from the front of the vehicle.
Cause: The condition may be caused by a loss of pre-load on the front wheel bearings due to the axle nut.
Correction: To diagnose the noise, re-torque the existing front axle shaft nut to 162 ft/lbs and test drive the vehicle. If the noise is eliminated, replace both front axle nuts with the updated part (P/N: 10257766). On vehicles equipped with the police package, add an additional Nord-Lock.
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